An isolated village literally built into the crevices and rock formations of a mountain.

Its appearance in "Game of Thrones" may spur on the long-awaited restoration of this medieval shipyard.

Stunning Roman aqueduct used for 1900 years and still standing.

A charming Spanish village sits atop this natural limestone overpass.

This awesome Spanish castle is so fantastical it was actually used on Game of Thrones.

This funky former tobacco factory is one of the most striking examples of Madrid's cultural diversity.

A Franco-era dam flooded (almost) everyone out of this centuries-old Aragonese town.

Considered the birthplace of the Copper Age and Bronze Age, the river is tinted red from 5,000 years of mining.

A gravity-defying "devil's bridge" that has a surprising architectural feature for its stability.

This amazing example of Valencian Art Nouveau looks more like a cathedral than a public market.

One of Antoni Gaudí’s earliest buildings, built between 1886 and 1890 for the industrialist Eusebi Güell.

A Spanish town built into the cliffs.

Occupied for six centuries by Franciscan Order nuns, this monastery is an amazing ode to Catalán Gothic architecture.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

This Navarrese cave's history of witchcraft and pagan ritual is not just embraced, but recreated each year.

Village situated on a narrow volcanic escarpment.

A landscape decorated with enormous skull sculptures.

The little church's beautifully frescoed ceiling has earned it the nickname “the Sistine Chapel of Madrid.”

The world's largest wooden structure.

One of Antoni Gaudí's least-visited works, an homage to Catalan patrimony that mixes neo-Gothic with Modernista forms.

Giant eggs, walls of bread, and nightmare surreality mark the largest collection of works by Salvador Dalí.

This whimsical winery by Antoni Gaudí looks ripped from the pages of a fairytale.

These magnificent city walls rise from the barren sun-baked Spanish plains like something straight out of a fairytale.

Natural stone arches form a walkable "cathedral" at low tide, then disappear entirely when the water returns.